1. Field of the Invention
The present invention relates to an information recording/reproducing apparatus having a mechanism for automatically loading a recording medium (hereinafter referred to as "auto-loading mechanism").
2. Description of the Related Art
Recently, information recording/reproducing apparatuses, which employ recording media allowing at least one of a recording operation and a reproducing operation to be performed, such as a write-once read-many optical disk and a photo-electro-magnetic type or a phase change type rewritable optical disk, have widely used.
A recording medium employed in these apparatuses is heavier than that employed in a floppy disk drive (FDD), and a driving unit for the recording medium rotates at high speed. Thus, the inertia force is great and about several seconds are needed for stopping or starting the medium driving unit.
When a recording medium is ejected from the FDD, the media is light, the speed of rotation of the medium is low and therefore the inertia force of the medium is weak. Thus, even if the medium is ejected while the driving unit is still rotating, no damage is caused to the driving unit or medium. When an eject switch is turned on, the eject operation and the operation for stopping the driving unit can be performed simultaneously.
On the other hand, the inertia force of the recording medium (e.g. optical disk) employed in the information recording/reproducing apparatus is great. If the medium is ejected while the driving unit rotates, the driving unit or medium is damaged. In this case, for example, the medium comes into contact with the head unit or cartridge, and as a result the medium is damaged. In addition, in the apparatus using the optical disk, etc., a considerable amount of time is needed to stop and start the medium driving unit. Thus, it is not possible to perform the eject operation simultaneously with the depression of the eject switch.
To solve this problem, an auto-eject mechanism is employed to eject the recording medium. According to the auto-eject mechanism, the information recording/reproducing apparatus itself performs a stop operation for stopping the driving unit when the depression by the operator of the eject switch provided on the front face of the information recording/reproducing apparatus is detected or when an eject command from an upper-level host computer is detected, and the medium is automatically ejected after the rotation of the medium is stopped.
The information recording/reproducing apparatus may be provided with an auto-loading mechanism. According to this mechanism, the information recording/reproducing apparatus itself automatically loads the recording medium in the apparatus, when the insertion of the recording medium in the information recording/reproducing apparatus is detected or when the depression of a loading switch (or a loading/eject switch having both functions of rejecting loading and ejecting) for requesting loading of the medium when the medium is in the eject position is detected.
Jap. Pat. Appln. KOKAI Publication No. 3-127377 discloses an example of the information recording/reproducing apparatus employing the auto-loading mechanism. In this apparatus, when a recording medium is left in the eject position for a predetermined time, the medium is automatically loaded in the information recording/reproducing apparatus. In this apparatus, the auto-loading is effected in order to prevent dust, etc. from entering the apparatus through the medium insertion port when the recording medium is left in the eject position for a long time.
When a data file recorded on the recording medium mounted in this information recording/reproducing apparatus is reproduced, when a new file is produced on the medium or when a file is updated, or when a file is deleted it is necessary to instantaneously access to a designated position according to a command from an upper-level host computer. However, as described above, in the apparatus using the optical disk, several seconds are needed to start the driving unit. If the driving unit is stopped, a predetermined location on the medium cannot be accessed immediately. Thus, the conventional information recording/reproducing apparatus is designed such that the driving unit is started immediately after the medium is mounted and, when the medium is mounted, the apparatus is always set in the "ready" state in which data reproduction, data recording and data erasure can be performed.
As described above, the conventional information recording/reproducing apparatus is set in the ready state when the recording medium is mounted, whether or not the medium is accessed immediately. In the ready state, for example, the driving unit for rotating the medium is rotating, the laser for recording/reproducing information is being turned on, and the focusing servo or tracking servo for focusing the laser beam on the recording surface of the medium or making the laser beam scan a predetermined track. Consequently, excess power is consumed, or the life of structural parts such as a laser and the life of the information recording/reproducing apparatus are shortened.